The impact of macular laser photocoagulation on contrast sensitivity function in patients with clinically significant macular edema.

BACKGROUND: Contrast sensitivity is an important aspect of visual function and is even more important for ordinary daily tasks than visual acuity. Contrast sensitivity function may be deteriorated to a significant level in diabetic retinopathy, especially in diabetic macular edema. The objective of this study was to determine the impact of macular laser photocoagulation-as the standard treatment of clinically significant macular edema-on contrast sensitivity function. METHODS: In a prospective noncomparative interventional case series, 17 patients with clinically significant bilateral macular edema and no history of prior macular laser photocoagulation were enrolled. Baseline visual acuity, contrast sensitivity function, and fluorescein angiography were obtained and reassessed three months after macular laser photocoagulation. RESULTS: Clinically significant macular edema resolved in 22 (65%) of 34 eyes, three months after their first session of macular laser photocoagulation. The mean pretreatment visual acuity was 24.5/40 (0.21 logMAR) +/-10.3/40. Three months after macular photocoagulation, visual acuity remained stable in 19 eyes, decreased in 12 eyes, and increased in three eyes. The mean post-treatment visual acuity was 24/40 (0.24 logMAR) +/-10.8/40. There was a statistically significant (P = 0.02) decrease in visual acuity following laser therapy. In subgroup analysis, this decrease in visual acuity was only observed in those with unresolved clinically significant macular edema. The mean contrast sensitivity threshold increased in all spatial frequencies by three months after macular photocoagulation. The maximum rise was observed in the frequency of 6.4 cycles per degree in the mid range of frequencies, with a pretreatment mean of 9.41 dB and a post-treatment mean of 11.50 dB (P<0.05). CONCLUSION: Contrast sensitivity function improved after macular laser photocoagulation in clinically significant macular edema patients.

CYP1B1 mutation profile of Iranian primary congenital glaucoma patients and associated haplotypes.

The mutation spectrum of CYP1B1 among 104 primary congenital glaucoma patients of the genetically heterogeneous Iranian population was investigated by sequencing. We also determined intragenic single nucleotide polymorphism (SNP) haplotypes associated with the mutations and compared these with haplotypes of other populations. Finally, the frequency distribution of the haplotypes was compared among primary congenital glaucoma patients with and without CYP1B1 mutations and normal controls. Genotype classification of six high-frequency SNPs was performed using the PHASE 2.0 software. CYP1B1 mutations in the Iranian patients were very heterogeneous. Nineteen nonconservative mutations associated with disease, and 10 variations not associated with disease were identified. Ten mutations and three variations not associated with disease were novel. The 13 novel variations make a notable contribution to the approximately 70 known variations in the gene. CYP1B1 mutations were identified in 70% of the patients. The four most common mutations were G61E, R368H, R390H, and R469W, which together constituted 76.2% of the CYP1B1 mutated alleles found. Six unique core SNP haplotypes were identified, four of which were common to the patients with and without CYP1B1 mutations and controls studied. Three SNP blocks determined the haplotypes. Comparison of haplotypes with those of other populations suggests a common origin for many of the mutations.

Oral Doxycycline Reduces the Total Number of Intraocular Bevacizumab Injections Needed to Control Neovascular Age-related Macular Degeneration.

Tetracyclines, especially doxycycline, play a role in the regulation of inflammation, immunomodulation, cell proliferation, and angiogenesis. Treatment of corneal angiogenesis or choroidal neovascularization with tetracyclines has been shown to be effective in animal models. The aim of this study was to evaluate the efficacy of oral doxycycline in reducing the total number of intraocular injections needed for controlling neovascular age-related macular degeneration in human patients. In this interventional case series, 28 random consecutive patients with neovascular age-related macular degeneration from Farabi Eye Hospital, Tehran, Iran were treated for 4 months with 200 mg doxycycline once a day after the first intravitreal bevacizumab injection in addition to standard therapy in agreement with as-needed regimen. After 12 months of follow-up, total number of injections, foveal thickness and visual acuity were compared to those at baseline and of similar studies. Similar to standard treatment, co-treatment with doxycycline was able to control active disease (intraretinal or subretinal fluid or leakage, new-onset of macular hemorrhage, and reduction of visual acuity more than 5 letters based on Early Treatment Diabetic Retinopathy Study [ETDRS] charts) yet with fewer injections (for current study and standard treatment, respectively 3.14 vs. 5.92, P < 0.001). Furthermore, while better control of the foveal thickness was achieved (P < 0.001), vision improvement was similar to that achieved with standard therapy (P > 0.05). If confirmed in larger studies, the findings of this interventional case series could provide a strategy to control neovascular age-related macular degeneration with fewer intraocular bevacizumab injections by co-administering a well-known oral agent-doxycycline.